When Satellites Collide, Confusion Follows

The unprecedented crash of two major satellites had aeronautics experts around the world scratching their heads today.

Yesterday, an operational U.S. Iridium communications satellite plowed into a defunct Russian military communications satellite some 800 kilometers (500 miles) above the skies over Siberia, smashing both into pieces. The impact has left a debris field traveling at 200 meters per second in an elliptical orbit 500 to 1300 kilometers overhead, according to an article from the Associated Press.

The AP account states that Iridium Satellite LLC, based in Bethesda, Md., claims that it was not responsible for the high-altitude collision; but a prominent Russian space expert said that he did not understand how Iridium and its government space partners, such as NASA, could have missed the presence of the slower satellite in its direct path--and taken action to prevent the accident.

"It could have been a computer failure or a human error," Igor Lisov told the AP. "It also could be that they only were paying attention to smaller debris and ignoring the defunct satellites." Lisov noted the debris could threaten a significant number of earth-tracking and weather satellites in similar orbits. "The other 65 Iridium satellites in similar orbits will face the most serious risk, and there are numerous earth-tracking and weather satellites in nearby orbits," he added.

In a press release posted to its website today, Iridium said that it "expects to move one of its in-orbit spare satellites into the network constellation to permanently replace the lost satellite."

A NASA spokesperson said the agency will need weeks to study the crash before it could render a threat assessment on the new debris field. However, NASA told the AP that it poses little risk to the International Space Station and its three-member crew, who are in a much lower orbit.

Comments

IEEE Spectrum’s general technology blog, featuring news, analysis, and opinions about engineering, consumer electronics, and technology and society, from the editorial staff and freelance contributors.